1. Technical Field
The present invention is related to new, water soluble derivatives of taxol with antineoplastic activity. More particularly, the present invention is related to 2'-O-acyl derivatives of taxol with improved water solubility while retaining antineoplastic property of the parent compound and methods of preparing the same.
2. State of the Art
The diterpene taxol was first isolated in 1971 from the Western Yew, Taxus brevifolia Nut by Wani et al (J. Amer. Chem. Soc. 46:1469, 1981), who established its structure by chemical and X-ray crystallographic methods. Numerous studies have indicated that taxol and various taxane derivatives are highly cytotoxic and possess strong in vivo activity in a number of test systems. The mechanism of action of taxol has been extensively studied and is summarized by Horwitz (Pharmacol. Ther. 25:83, 1984). Briefly, taxol is a unique antimitotic agent which acts by promoting tubulin assembly into stable aggregated structures which resist depolymerization by dilution, calcium ion, cold, and a number of microtubule-disrupting drugs. The formulation of taxol for antitumor testing has been difficult due to its extremely low aqueous solubility, and lack of functional groups that would allow salt formation.